The present invention relates to a circulatory assist system.
In general, in a conventional circulatory assist system a blood pump is expected to be inflated and deflated alternately by introducing and discharging a shuttle gas, respectively, from a driving device via a tube. During deflation of the blood pump, an outer surface of the blood pump is in contact with the blood of a patient and the pressure within the blood pump is less than that of the blood per so that the thin membrane or film of the raw material of the blood pump allows vapour in the blood to enter into the shuttle gas. The resultant vapour enters the tube and is formed into water drops which are apt to disturb the flow of the shuttle gas. For avoiding such a problem, a drain device is provided in the circulatory assist system in order that the water drops fall into the drain device.
in Japanese Patent Laid-open Print No. Hei 3, (1991)-63068 published on Mar. 19, 1991 without examination, the water drops fall by gravity into a drain device. An outlet of the driving device through which the shuttle gas passes, the tube except for a portion at which the blood pump is connected and the drain device should be extended along a vertical line. Thus, the position of the drain device is fixed in effect. This means that if the drain device is located at an unexpected position, the water drops rail to fall into the drain device and remain in the tube which leads to a disturbance of the flow of the shuttle gas.